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Date: Fri, 28 Jul 2017 18:28:13 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Prarit Bhargava <prarit@redhat.com>
cc: Peter Zijlstra <peterz@infradead.org>, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH 2/2] printk: Add boottime and real timestamps
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On Fri, 28 Jul 2017, Prarit Bhargava wrote:
> On 07/25/2017 09:00 AM, Peter Zijlstra wrote:
> Thanks for the above change.  I can see that makes the code simpler.
> 
> > Although I must strongly discourage using REALTIME, DST will make
> > untangling your logs an absolute nightmare. I would simply not provide
> > it.
> 
> I understand your concern, however, I've been in situations where REALTIME
> stamping has pointed me in the direction of where a bug was.  Even with the
> complicated logs I think it is worthwhile.

As Mark pointed out. ktime_get_real() and the fast variant return UTC. The
timezone mess plus the DST nonsense are done in user space.

Thanks,

	tglx